Methacrylamide

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Japanese government peer-reviewed the documents, audited selected studies.

Qualifier:

according to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Supplier: KISHIDA CHEMICALS CO., Ltd (Lot No. D12358J)
Purity: >= 98 %

Analytical monitoring:

yes

Details on sampling:

SAMPLING: daily during exposure

Vehicle:

no

Details on test solutions:

Dilution water: medium on OECD Test guideline 211

Test organisms (species):

Daphnia magna

Details on test organisms:

Test Organism:
-supplier; National Institute of Environmental Studies (Japan)
-age; juvenile Daphnia magna less than 24hr old
–feeding during acclimation: Chlorella vulgaris, 0.1 - 0.2 mgC/day/individual
–acclimation: 3-4 weeks
–feeding during test: Chlorella vulgaris, 0.1 - 0.2 mgC/day/individual

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

21 d

Hardness:

245 mg/l as CaCO3

Test temperature:

19 - 21 °C

pH:

7.6

Salinity:

no data

Nominal and measured concentrations:

0, 100.0 mg/L nominal (actual concentration measured and greater than 80% of the nominal)

Details on test conditions:

TEST SYSTEM
-renewal of test solution: 3 times a week
-exposure vessel type: 80 mL test solution in a 100 mL glass vessel
-number of replicates/individual per replicate: 10/1
-intensity of irradiation: room light
-photoperiod: 16hr - 8hr light-dark cycle

Reference substance (positive control):

yes

Remarks:

K2Cr2O7

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

reproduction

Details on results:

Results: Table 1 NOMINAL/MEASURED CONCENTRATION:
-----------------------------------------------------------
Nominal Measured conc. (mg/L) Time
conc. 0day 2day 6day 8day 15day 17day weighted
* ** * ** * ** mean
-----------------------------------------------------------
Control <0.5 <0.5 <0.5 <0.5 <0.5 <0.5 <0.5
100.0mg/L 92.5 91.3 99.5 93.6 104.1 100.2 96.9 %
of nominal 92.5 91.3 99.5 93.6 104.1 100.2 96.9
-----------------------------------------------------------
* : freshly prepared test solution
**: test solution after 48hr exposure period

EFFECT DATA (PARENTS)
21day LC50 > 100.0 mg/L
EFFECT DATA (REPRODUCTION)
21day EC50 > 100.0 mg/L
21day NOEC > 100.0 mg/L
21day LOEC > 100.0 mg/L

Table 2 CUMULATIVE NUMBERS OF DEAD PARENTAL DAPHNIA AND
MORTALITY AFTER EXPOSURE OF 21DAY
-----------------------------------------------------------
Nominal Conc. Number of dead Mortality (%)
-----------------------------------------------------------
Control 1 10
100.0 mg/L 2 20
-----------------------------------------------------------
Table 3 TIME (day) TO FIRST BROOD PRODUCTION
-----------------------------------------------------------
Nominal Conc. vessel no. Mean day
1 2 3 4 5 6 7 8 9 10
-----------------------------------------------------------
Control 8 11 7 18 8 20 13 10 - 11 11.8
100.0mg/L 13 17 - 8 11 7 11 17 11 - 11.9
-----------------------------------------------------------
Table 4 MEAN CUMULATIVE NUMBER OF JUVENILES PRODUCED PER ADULT AND
INHIBITION RATE DURING EXPOSURE
-----------------------------------------------------------
Nominal DAY
Conc. 1-6 7 8 9 10 11 12 13 14 15 16
-----------------------------------------------------------
Control 0.0 0.2 0.9 0.9 1.3 4.0 4.0 12.4 18.4 18.4 25.4
100.mg/L0.0 0.4 0.9 0.9 0.9 3.8 3.8 4.8 6.8 6.8 6.8
-----------------------------------------------------------
-----------------------------------------------------------
Nominal DAY mean+/-S.D. Inhibition
Conc.17 18 19 20 21 rate (%)
-----------------------------------------------------------
Control 39.1 39.4 43.8 64.2 66.6 66.6+/-39.72 -
100.0mg/L 31.6 31.6 31.6 66.1 66.1 66.1+/-16.85 0.8
-----------------------------------------------------------

Table 5 CUMULATIVE NUMBER OF JUVENILES PRODUCED PER
ADULT DURING EXPOSURE
-------------------------------------------------------------------------------------------------
Nominal Conc. vessel no. Total
1 2 3 4 5 6 7 8 9 10
------------------------------------------------------------------------------------------------
Control 51 71 42 24 109 7 114 66 - 115 599
100.0mg/L 39 74 - 51 57 78 92 64 74 - 529
------------------------------------------------------------------------------------------------

NUMBER OF WINTER EGGS DURING EXPOSURE
none of winter eggs at Control and 100.0 mg/L

Results with reference substance (positive control):

EiC50 (48hrs) = 0.60 mg/l , K2Cr2O7

Reported statistics and error estimates:

Statistics: F&t-test; Yukms StatLight#3 "Pairwise Comparison"

Validity criteria fulfilled:

yes

Conclusions:

Methacrylamide was tested in a Daphnia magna Reproduction test, OECD 211, 21 d. The NOEC of reproduction is > 100 mg/l (measuerd and nominal)

Executive summary:

The 21-day-chronic toxicity of methacrylamide to Daphnia magna was studied under static renewal conditions.  Daphnids were exposed to control and test chemical at nominal/measured concentrations of 100 mg a.i./L.  The 21 day LC₅₀/EC₅₀based on mortality/sublethal effect was > 100 mg a.i./L.  The 21-day NOEC based on sublethal effect was >100 mg a.i./L.  The sublethal effects included were reproduction.  Production of offsprings in the treated groups indicated that methacrylamide did not have an effect on the reproduction at concentrations greater than > 100 mg a.i./L. 

This study is classified as acceptable and satisfies the guideline requirements for a chronic toxicity study with freshwater invertebrates.

Results Synopsis

Test organism: juvenile Daphnia magna less than 24 hr old

Test type: Static renewal

Description of key information

The 21-day-chronic toxicity of methacrylamide to Daphnia magna was studied under static renewal conditions. Daphnids were exposed to control and test chemical at nominal/measured concentrations of 100 mg a.i./L.  The 21 day LC₅₀/EC₅₀based on mortality/sublethal effect was > 100 mg a.i./L.  The 21-day NOEC based on sublethal effect was >100 mg a.i./L.  The sublethal effects included were reproduction.  Production of offsprings in the treated groups indicated that methacrylamide did not have an effect on the reproduction at concentrations greater than > 100 mg a.i./L. 

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L